The more times you lose weight and then gain it back, the harder it is to lose pounds on your next attempt. Not necessarily, says Glenn Gaesser, Ph.D., a weight-loss researcher and professor of exercise physiology at the University of Virginia in Charlottesville. "Many people spend their whole lives going through yo-yo weight cycles." he says. "But there's no definitive data that shows it will permanently slow your metabolism [the rate at which your body burns food for energy]."
But rebound pounds do tend to make you fatter when it comes to body composition, especially if you go on crash diets. For example, say you toggle between 150 and 135 pounds-- lose 15 pounds your regain likely consist of more fat and less muscle than you originally lost, Gaesser says: "Most people who lose weight rapidly will lose muscle mass." Rebound pounds usually contain more fat, less muscle. N.G.
I personally believe that exercising the large muscle groups three times a week and alternating days of weight resistance training will prevent muscle loss and burn off the fat as an extra bonus. (Remember if your carbohydrate intake is too low and your ketones are high your body will be burning your muscles as fuel.)
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